<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>jquery源码解析视频74-1</title>
    <script src="../jquery-2.0.3.js"></script>

</head>

<body>
    <!-- <ul>
        <li></li>
        <li></li>
        <li></li>
    </ul>
    <ol>
        <li></li>
        <li></li>
        <li></li>
    </ol> -->


    <div class="box">div1</div>
    <div>div2</div>

    <script>
        $(function () {
            // $("li").css("background", "red");
            // find
            // $("ul").find("li").css("background", "red");

            // console.log($("div").is(".box")); // 判断两个div中有没有.box元素，有就返回true
            // console.log($("div:first").is(".box"));
            // console.log($("div:last").is(".box"));
        });
    </script>

</body>

</html>